To biologically mimic the carbohydrate-protein interactions in artificial systems, one of the challenges is to construct a glycosylated surface with a high glycosyl density to yield a notable 'glycoside cluster effect'. A novel strategy is presented for high density glycosylation of the surface of a microporous poly(propylene) membrane (MPPM) by click chemistry. It is promising that the surface glycosyl density can be well controlled over a wide range and the maximum value is over 10 mu mol.cm(-2). The recognition capability of these glycosylated MPPMs to lectins indicates the occurrence of the 'glycoside cluster effect' when the glycosyl density on the membrane surface exceeds 0.20 mu mol.cm(-2).